A general rule of thumb when it comes to wrinkles is that they are most prevalent at the joints (Elbow, shoulder, wrist, knee and waist, etc.) and kind of have a sort of ‘Z’ formation (Only clothing artists will probably get this, there’s videos online to help you out).

It looks decent, I’d personally get rid of the grey outlines at the end of the sleeves however, since they clash with the coloration of the rest of the shirt greatly and look unnaturally geometrically jagged (Not like a fabric tear, which I think is what you are going for). I’d look up reference images for this sort of stuff.

Great work though, you’ve definitely improved. Hope this helps